Modelling the Effect of Road Grade on the CO2 and NOx Emissions of a Passenger Car through a Real World-Urban Traffic Network

A Portable Emission Measurement System (PEMS) was utilised to record the on-road Carbon Dioxide (CO2) emission of a EURO 4 petrol vehicle over 48 test runs through an urban-traffic network. The tests were conducted over a 780 metre micro-scale road segment between Headingley and the City of Leeds, UK, with measurement on both the inbound (Section A) and outbound lanes (Section B). The monitored test runs were conducted under a range of traffic flow conditions from heavily congested to free-flowing traffic. Vehicle exhaust emission simulations using an instantaneous power-emission model have the capability to generate estimates of real-world vehicle emissions over micro-scale road sections. The Technical University of Graz’s (TUG) Passenger car and Heavy duty Emission Model (PHEM) was used to calculate a CO2 emission estimate for each of the 48 test runs through Sections A and B. The model CO2 emission estimates were then compared to the real-world PEMS emission measurements, to determine the accuracy of the modelling methodology. Whilst instrumented vehicles can adequately capture second-by-second (1Hz) absolute position and vehicle speed there is significant instrument error in the measurement of real-world elevation using a Global Positioning System (GPS) as part of a PEMS set-up. These errors make it very difficult to accurately calculate a 1Hz road grade with GPS systems. However, as road grade can have an important influence on engine power demand and hence fuel consumption and exhaust emission it is essential to include a representative road grade estimate for micro-scale emission estimation. Rather than using a GPS recorded elevation, this study developed a simple road grade estimation methodology which employs Geographic Information System (GIS) software to interpolate the elevation at each second of PEMS data from a 5-metre resolution Digital Terrain Map (DTM) derived from Light Detection And Ranging (LiDAR) data. The method applies an algorithm to compute the road grade from the LiDAR-GIS elevation values and vehicle speed, and alleviates errors resulting from absolute position measurement inaccuracy of the GPS at low speed. The addition of the LiDAR-GIS road grade to the PHEM modelling was found to improve the accuracy of the PHEM estimate of the PEMS measured real-world CO2 emission. From the 48 test runs the average PHEM estimate (including road grade) of the real-world measured CO2 emission through Section A was 93%, and through Section B was 94%. Of the total 96 test runs over Section A and B 91% of the PHEM estimates were between 80% and 110% of the PEMS recorded value. In further analysis, an assessment of the effect of road grade on both CO2 and NOx emission was conducted. Sections A and B were combined for each test run to form Segment AB, which has a net flat road grade. The PEMS recorded speed profiles for each of the test runs through sections A and B were input into PHEM and emission estimates generated under four road grade scenarios. The scenarios were formed by decreasing and exaggerating the LiDAR-GIS road grade for each second of data, multiplying it by coefficients of 0 (flat), 0.5 (half the grade), 1, and 2 (double the grade). The results indicate that assuming a flat profile in PHEM would result in an average underestimate of the segment emission by 2.7% for CO2 and 7.0% for NOx when calculated with road grade, and by 7.9% for CO2 and 20.4% for NOx were the road grade doubled. The method developed in this study provides a simple methodology for calculating 1Hz road grade, and has been shown to improve the modelling of CO2 emission for this data set. This research suggest that using the PHEM model with a LiDAR-GIS calculated road grade provides a practical method for accurately estimating real-world micro-scale emission. On-road emission monitoring by PEMS is scheduled to be introduced for Euro 6c type approval from September 2017. In order to accurately determine road load during the real-world test procedure it will be important to develop a suitable methodology for calculating a 1Hz road grade

Bone Marrow Stem Cell Treatment for Ischemic Heart Disease in Patients with No Option of Revascularization: A Systematic Review and Meta-Analysis

PMCID: PMC3686792This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited

Research on edge-control methods in CNC polishing

Background: We have developed edge-control for the Precessions TM process suitable for fast fabrication of large mirror segments, and other applications sensitive to edge mis-figure. This has been applied to processing of European extremely large telescope (E-ELT) prototype mirror-segments, meeting the specification on maximum edge mis-figure. However we have observed residuals that have proved impossible to correct with this approach, being in part the legacy of asymmetries in the input edge-profiles. Methods: We have therefore compared different proposed methods experimentally and theoretically and report here on a new edge-rectification step, which operates locally on edges, does not disturb the completed bulk area. Results: A new toolpath has been developed and experiments have been carried out to demonstrate that local edge rectification can be carried out. Conclusions: With this method, the residue error on edges can be removed separately and has potential to reduce total process time

Associations of sitting accumulation patterns with cardio-metabolic risk biomarkers in Australian adults

Backgroun

Reduced functional measure of cardiovascular reserve predicts admission to critical care unit following kidney transplantation

Background: There is currently no effective preoperative assessment for patients undergoing kidney transplantation that is able to identify those at high perioperative risk requiring admission to critical care unit (CCU). We sought to determine if functional measures of cardiovascular reserve, in particular the anaerobic threshold (VO2AT) could identify these patients. Methods: Adult patients were assessed within 4 weeks prior to kidney transplantation in a University hospital with a 37-bed CCU, between April 2010 and June 2012. Cardiopulmonary exercise testing (CPET), echocardiography and arterial applanation tonometry were performed. Results: There were 70 participants (age 41.7614.5 years, 60% male, 91.4% living donor kidney recipients, 23.4% were desensitized). 14 patients (20%) required escalation of care from the ward to CCU following transplantation. Reduced anaerobic threshold (VO2AT) was the most significant predictor, independently (OR = 0.43; 95% CI 0.27–0.68; p,0.001) and in the multivariate logistic regression analysis (adjusted OR = 0.26; 95% CI 0.12–0.59; p = 0.001). The area under the receiveroperating- characteristic curve was 0.93, based on a risk prediction model that incorporated VO2AT, body mass index and desensitization status. Neither echocardiographic nor measures of aortic compliance were significantly associated with CCU admission. Conclusions: To our knowledge, this is the first prospective observational study to demonstrate the usefulness of CPET as a preoperative risk stratification tool for patients undergoing kidney transplantation. The study suggests that VO2AT has the potential to predict perioperative morbidity in kidney transplant recipients

Vascular disrupting agent for neovascular age related macular degeneration: a pilot study of the safety and efficacy of intravenous combretastatin A-4 phosphate

BACKGROUND: This study was designed to assess the safety, tolerability, and efficacy of intravenous infusion of CA4P in patients with neovascular age-related macular degeneration (AMD). METHODS: Prospective, interventional, dose-escalation clinical trial. Eight patients with neovascular AMD refractory to at least 2 sessions of photodynamic therapy received CA4P at a dose of 27 or 36 mg/m2 as weekly intravenous infusion for 4 consecutive weeks. Safety was monitored by vital signs, ocular and physical examinations, electrocardiogram, routine laboratory tests, and collection of adverse events. Efficacy was assessed using retinal fluorescein angiography, optical coherence tomography, and best corrected visual acuity (BCVA). RESULTS: The most common adverse events were elevated blood pressure (46.7%), QTc prolongation (23.3%), elevated temperature (13.3%), and headache (10%), followed by nausea and eye injection (6.7%). There were no adverse events that were considered severe in intensity and none resulted in discontinuation of treatment. There was reduction of the excess foveal thickness by 24.15% at end of treatment period and by 43.75% at end of the two-month follow-up (p = 0.674 and 0.161, respectively). BCVA remained stable throughout the treatment and follow-up periods. CONCLUSIONS: The safety profile of intravenous CA4P was consistent with that reported in oncology trials of CA4P and with the class effects of vascular disruptive agents; however, the frequency of adverse events was different. There are evidences to suggest potential efficacy of CA4P in neovascular AMD. However, the level of systemic safety and efficacy indicates that systemic CA4P may not be suitable as an alternative monotherapy to current standard-of-care therapy

Stochastic Gravity: Theory and Applications

Whereas semiclassical gravity is based on the semiclassical Einstein equation with sources given by the expectation value of the stress-energy tensor of quantum fields, stochastic semiclassical gravity is based on the Einstein-Langevin equation, which has in addition sources due to the noise kernel. In the first part, we describe the fundamentals of this new theory via two approaches: the axiomatic and the functional. In the second part, we describe three applications of stochastic gravity theory. First, we consider metric perturbations in a Minkowski spacetime, compute the two-point correlation functions of these perturbations and prove that Minkowski spacetime is a stable solution of semiclassical gravity. Second, we discuss structure formation from the stochastic gravity viewpoint. Third, we discuss the backreaction of Hawking radiation in the gravitational background of a black hole and describe the metric fluctuations near the event horizon of an evaporating black holeComment: 100 pages, no figures; an update of the 2003 review in Living Reviews in Relativity gr-qc/0307032 ; it includes new sections on the Validity of Semiclassical Gravity, the Stability of Minkowski Spacetime, and the Metric Fluctuations of an Evaporating Black Hol

Cumulative Lead Exposure and Tooth Loss in Men: The Normative Aging Study

Background: Individuals previously exposed to lead remain at risk because of endogenous release of lead stored in their skeletal compartments. However, it is not known if long-term cumulative lead exposure is a risk factor for tooth loss. Objectives: We examined the association of bone lead concentrations with loss of natural teeth. Methods: We examined 333 men enrolled in the Veterans Affairs Normative Aging Study. We used a validated K-shell X-ray fluorescence (KXRF) method to measure lead concentrations in the tibial midshaft and patella. A dentist recorded the number of teeth remaining, and tooth loss was categorized as 0, 1–8 or ≥ 9 missing teeth. We used proportional odds models to estimate the association of bone lead biomarkers with tooth loss, adjusting for age, smoking, diabetes, and other putative confounders. Results: Participants with ≥ 9 missing teeth had significantly higher bone lead concentrations than those who had not experienced tooth loss. In multivariable-adjusted analyses, men in the highest tertile of tibia lead (> 23 μg/g) and patella lead (> 36 μg/g) had approximately three times the odds of having experienced an elevated degree of tooth loss (≥ 9 vs. 0–8 missing teeth or ≥ 1 vs. 0 missing teeth) as those in the lowest tertile [prevalence odds ratio (OR) = 3.03; 95% confidence interval (CI), 1.60–5.76 and OR = 2.41; 95% CI, 1.30–4.49, respectively]. Associations between bone lead biomarkers and tooth loss were similar in magnitude to the increased odds observed in participants who were current smokers. Conclusion: Long-term cumulative lead exposure is associated with increased odds of tooth loss

Stochastic Gravity: Theory and Applications

Whereas semiclassical gravity is based on the semiclassical Einstein equation with sources given by the expectation value of the stress-energy tensor of quantum fields, stochastic semiclassical gravity is based on the Einstein-Langevin equation, which has in addition sources due to the noise kernel.In the first part, we describe the fundamentals of this new theory via two approaches: the axiomatic and the functional. In the second part, we describe three applications of stochastic gravity theory. First, we consider metric perturbations in a Minkowski spacetime: we compute the two-point correlation functions for the linearized Einstein tensor and for the metric perturbations. Second, we discuss structure formation from the stochastic gravity viewpoint. Third, we discuss the backreaction of Hawking radiation in the gravitational background of a quasi-static black hole.Comment: 75 pages, no figures, submitted to Living Reviews in Relativit